/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */

/* 
 * Copyright (C) 2001, 2002 Havoc Pennington
 * Copyright (C) 2002, 2003 Red Hat Inc.
 * Some ICCCM manager selection code derived from fvwm2,
 * Copyright (C) 2001 Dominik Vogt, Matthias Clasen, and fvwm2 team
 * Copyright (C) 2003 Rob Adams
 * Copyright (C) 2004-2006 Elijah Newren
 * Copyright (C) 2013 Red Hat Inc.
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */

#include "config.h"

#include <string.h>
#include <math.h>
#include <clutter/clutter.h>

#ifdef HAVE_RANDR
#include <X11/extensions/Xrandr.h>
#endif

#include <meta/main.h>
#include <meta/util.h>
#include "monitor-private.h"

#include "meta-dbus-xrandr.h"

struct _MetaMonitorManager
{
  GObject parent_instance;

  /* XXX: this structure is very badly
     packed, but I like the logical organization
     of fields */

  unsigned int serial;

  /* Outputs refer to physical screens,
     CRTCs refer to stuff that can drive outputs
     (like encoders, but less tied to the HW),
     while monitor_infos refer to logical ones.

     See also the comment in monitor-private.h
  */
  MetaOutput *outputs;
  unsigned int n_outputs;

  MetaMonitorMode *modes;
  unsigned int n_modes;

  MetaCRTC *crtcs;
  unsigned int n_crtcs;

  MetaMonitorInfo *monitor_infos;
  unsigned int n_monitor_infos;
  int primary_monitor_index;

#ifdef HAVE_RANDR
  Display *xdisplay;
#endif

  int dbus_name_id;
  MetaDBusDisplayConfig *skeleton;
};

struct _MetaMonitorManagerClass
{
  GObjectClass parent_class;
};

enum {
  MONITORS_CHANGED,
  SIGNALS_LAST
};

static int signals[SIGNALS_LAST];

G_DEFINE_TYPE (MetaMonitorManager, meta_monitor_manager, G_TYPE_OBJECT);

static void
make_dummy_monitor_config (MetaMonitorManager *manager)
{
  manager->modes = g_new0 (MetaMonitorMode, 1);
  manager->n_modes = 1;

  manager->modes[0].mode_id = 1;
  if (manager->xdisplay)
    {
      Screen *screen = ScreenOfDisplay (manager->xdisplay,
                                        DefaultScreen (manager->xdisplay));

      manager->modes[0].width = WidthOfScreen (screen);
      manager->modes[0].height = HeightOfScreen (screen);
    }
  else
    {
      manager->modes[0].width = 1024;
      manager->modes[0].height = 768;
    }
  manager->modes[0].refresh_rate = 60.0;

  manager->crtcs = g_new0 (MetaCRTC, 1);
  manager->n_crtcs = 1;

  manager->crtcs[0].crtc_id = 2;
  manager->crtcs[0].rect.x = 0;
  manager->crtcs[0].rect.y = 0;
  manager->crtcs[0].rect.width = manager->modes[0].width;
  manager->crtcs[0].rect.height = manager->modes[0].height;
  manager->crtcs[0].current_mode = &manager->modes[0];

  manager->outputs = g_new0 (MetaOutput, 1);
  manager->n_outputs = 1;

  manager->outputs[0].crtc = &manager->crtcs[0];
  manager->outputs[0].output_id = 3;
  manager->outputs[0].name = g_strdup ("LVDS");
  manager->outputs[0].vendor = g_strdup ("unknown");
  manager->outputs[0].product = g_strdup ("unknown");
  manager->outputs[0].serial = g_strdup ("");
  manager->outputs[0].width_mm = 222;
  manager->outputs[0].height_mm = 125;
  manager->outputs[0].subpixel_order = COGL_SUBPIXEL_ORDER_UNKNOWN;
  manager->outputs[0].preferred_mode = &manager->modes[0];
  manager->outputs[0].n_modes = 1;
  manager->outputs[0].modes = g_new0 (MetaMonitorMode *, 1);
  manager->outputs[0].modes[0] = &manager->modes[0];
  manager->outputs[0].n_possible_crtcs = 1;
  manager->outputs[0].possible_crtcs = g_new0 (MetaCRTC *, 1);
  manager->outputs[0].possible_crtcs[0] = &manager->crtcs[0];
}

#ifdef HAVE_RANDR

static void
read_monitor_infos_from_xrandr (MetaMonitorManager *manager)
{
    XRRScreenResources *resources;
    RROutput primary_output;
    unsigned int i, j, k;
    unsigned int n_actual_outputs;

    resources = XRRGetScreenResourcesCurrent (manager->xdisplay,
                                              DefaultRootWindow (manager->xdisplay));
    if (!resources)
      return make_dummy_monitor_config (manager);

    manager->n_outputs = resources->noutput;
    manager->n_crtcs = resources->ncrtc;
    manager->n_modes = resources->nmode;
    manager->outputs = g_new0 (MetaOutput, manager->n_outputs);
    manager->modes = g_new0 (MetaMonitorMode, manager->n_modes);
    manager->crtcs = g_new0 (MetaCRTC, manager->n_crtcs);

    for (i = 0; i < (unsigned)resources->nmode; i++)
      {
        XRRModeInfo *xmode = &resources->modes[i];
        MetaMonitorMode *mode;

        mode = &manager->modes[i];

        mode->mode_id = xmode->id;
        mode->width = xmode->width;
        mode->height = xmode->height;
        mode->refresh_rate = (xmode->dotClock /
                              ((float)xmode->hTotal * xmode->vTotal));
      }

    for (i = 0; i < (unsigned)resources->ncrtc; i++)
      {
        XRRCrtcInfo *crtc;
        MetaCRTC *meta_crtc;

        crtc = XRRGetCrtcInfo (manager->xdisplay, resources, resources->crtcs[i]);

        meta_crtc = &manager->crtcs[i];

        meta_crtc->crtc_id = resources->crtcs[i];
        meta_crtc->rect.x = crtc->x;
        meta_crtc->rect.y = crtc->y;
        meta_crtc->rect.width = crtc->width;
        meta_crtc->rect.height = crtc->height;

        for (j = 0; j < (unsigned)resources->nmode; j++)
          {
            if (resources->modes[j].id == crtc->mode)
              {
                meta_crtc->current_mode = &manager->modes[j];
                break;
              }
          }

        XRRFreeCrtcInfo (crtc);
      }

    primary_output = XRRGetOutputPrimary (manager->xdisplay,
                                          DefaultRootWindow (manager->xdisplay));

    n_actual_outputs = 0;
    for (i = 0; i < (unsigned)resources->noutput; i++)
      {
        XRROutputInfo *output;
        MetaOutput *meta_output;

        output = XRRGetOutputInfo (manager->xdisplay, resources, resources->outputs[i]);

        meta_output = &manager->outputs[n_actual_outputs];

        if (output->connection != RR_Disconnected)
          {
            meta_output->output_id = resources->outputs[i];
            meta_output->name = g_strdup (output->name);
            /* FIXME: to fill useful values for these we need an EDID parser */
            meta_output->vendor = g_strdup ("unknown");
            meta_output->product = g_strdup ("unknown");
            meta_output->serial = g_strdup ("");
            meta_output->width_mm = output->mm_width;
            meta_output->height_mm = output->mm_height;
            meta_output->subpixel_order = COGL_SUBPIXEL_ORDER_UNKNOWN;

            meta_output->n_modes = output->nmode;
            meta_output->modes = g_new0 (MetaMonitorMode *, meta_output->n_modes);
            for (j = 0; j < meta_output->n_modes; j++)
              {
                for (k = 0; k < manager->n_modes; k++)
                  {
                    if (output->modes[j] == (XID)manager->modes[k].mode_id)
                      {
                        meta_output->modes[j] = &manager->modes[k];
                        break;
                      }
                  }
              }
            meta_output->preferred_mode = meta_output->modes[0];

            meta_output->n_possible_crtcs = output->ncrtc;
            meta_output->possible_crtcs = g_new0 (MetaCRTC *, meta_output->n_possible_crtcs);
            for (j = 0; j < (unsigned)output->ncrtc; j++)
              {
                for (k = 0; k < manager->n_crtcs; k++)
                  {
                    if ((XID)manager->crtcs[k].crtc_id == output->crtcs[j])
                      {
                        meta_output->possible_crtcs[j] = &manager->crtcs[k];
                        break;
                      }
                  }
              }

            meta_output->crtc = NULL;
            for (j = 0; j < manager->n_crtcs; j++)
              {
                if ((XID)manager->crtcs[j].crtc_id == output->crtc)
                  {
                    meta_output->crtc = &manager->crtcs[j];
                    break;
                  }
              }

            meta_output->is_primary = ((XID)meta_output->output_id == primary_output);
            meta_output->is_presentation = FALSE;

            n_actual_outputs++;
          }

        XRRFreeOutputInfo (output);
      }

    manager->n_outputs = n_actual_outputs;

    XRRFreeScreenResources (resources);
}

#endif

/*
 * meta_has_dummy_output:
 *
 * Returns TRUE if the only available monitor is the dummy one
 * backing the ClutterStage window.
 */
static gboolean
has_dummy_output (void)
{
  return FALSE;
}

static void
meta_monitor_manager_init (MetaMonitorManager *manager)
{
}

static gboolean
make_debug_config (MetaMonitorManager *manager)
{
  const char *env;

  env = g_getenv ("META_DEBUG_MULTIMONITOR");

  if (env == NULL)
    return FALSE;

#ifdef HAVE_RANDR
  if (strcmp (env, "xrandr") == 0)
    read_monitor_infos_from_xrandr (manager);
  else
#endif
    make_dummy_monitor_config (manager);

  return TRUE;
}

static void
read_current_config (MetaMonitorManager *manager)
{
  if (make_debug_config (manager))
    return;

  if (has_dummy_output ())
    return make_dummy_monitor_config (manager);

#ifdef HAVE_RANDR
  return read_monitor_infos_from_xrandr (manager);
#endif
}

/*
 * make_logical_config:
 *
 * Turn outputs and CRTCs into logical MetaMonitorInfo,
 * that will be used by the core and API layer (MetaScreen
 * and friends)
 */
static void
make_logical_config (MetaMonitorManager *manager)
{
  GArray *monitor_infos;
  unsigned int i, j;

  monitor_infos = g_array_sized_new (FALSE, TRUE, sizeof (MetaMonitorInfo),
                                     manager->n_outputs);

  /* Walk the list of MetaCRTCs, and build a MetaMonitorInfo
     for each of them, unless they reference a rectangle that
     is already there.
  */
  for (i = 0; i < manager->n_crtcs; i++)
    {
      MetaCRTC *crtc = &manager->crtcs[i];

      /* Ignore CRTCs not in use */
      if (crtc->current_mode == NULL)
        continue;

      for (j = 0; j < monitor_infos->len; j++)
        {
          MetaMonitorInfo *info = &g_array_index (monitor_infos, MetaMonitorInfo, i);
          if (meta_rectangle_equal (&crtc->rect,
                                    &info->rect))
            {
              crtc->logical_monitor = info;
              break;
            }
        }

      if (crtc->logical_monitor == NULL)
        {
          MetaMonitorInfo info;

          info.number = monitor_infos->len;
          info.rect = crtc->rect;
          info.is_primary = FALSE;
          /* This starts true because we want
             is_presentation only if all outputs are
             marked as such (while for primary it's enough
             that any is marked)
          */
          info.is_presentation = TRUE;
          info.in_fullscreen = -1;
          info.output_id = 0;

          g_array_append_val (monitor_infos, info);

          crtc->logical_monitor = &g_array_index (monitor_infos, MetaMonitorInfo,
                                                  info.number);
        }
    }

  /* Now walk the list of outputs applying extended properties (primary
     and presentation)
  */
  for (i = 0; i < manager->n_outputs; i++)
    {
      MetaOutput *output;
      MetaMonitorInfo *info;

      output = &manager->outputs[i];

      /* Ignore outputs that are not active */
      if (output->crtc == NULL)
        continue;

      /* We must have a logical monitor on every CRTC at this point */
      g_assert (output->crtc->logical_monitor != NULL);

      info = output->crtc->logical_monitor;

      info->is_primary = info->is_primary || output->is_primary;
      info->is_presentation = info->is_presentation && output->is_presentation;

      if (output->is_primary || info->output_id == 0)
        info->output_id = output->output_id;

      if (info->is_primary)
        manager->primary_monitor_index = info->number;
    }

  manager->n_monitor_infos = monitor_infos->len;
  manager->monitor_infos = (void*)g_array_free (monitor_infos, FALSE);
}

static MetaMonitorManager *
meta_monitor_manager_new (Display *display)
{
  MetaMonitorManager *manager;

  manager = g_object_new (META_TYPE_MONITOR_MANAGER, NULL);

  manager->xdisplay = display;

  read_current_config (manager);
  make_logical_config (manager);
  return manager;
}

static void
free_output_array (MetaOutput *old_outputs,
                   int         n_old_outputs)
{
  int i;

  for (i = 0; i < n_old_outputs; i++)
    {
      g_free (old_outputs[i].name);
      g_free (old_outputs[i].vendor);
      g_free (old_outputs[i].product);
      g_free (old_outputs[i].serial);
      g_free (old_outputs[i].modes);
      g_free (old_outputs[i].possible_crtcs);
    }

  g_free (old_outputs);
}

static void
meta_monitor_manager_finalize (GObject *object)
{
  MetaMonitorManager *manager = META_MONITOR_MANAGER (object);

  free_output_array (manager->outputs, manager->n_outputs);
  g_free (manager->monitor_infos);
  g_free (manager->modes);
  g_free (manager->crtcs);

  G_OBJECT_CLASS (meta_monitor_manager_parent_class)->finalize (object);
}

static void
meta_monitor_manager_dispose (GObject *object)
{
  MetaMonitorManager *manager = META_MONITOR_MANAGER (object);

  if (manager->dbus_name_id != 0)
    {
      g_bus_unown_name (manager->dbus_name_id);
      manager->dbus_name_id = 0;
    }

  g_clear_object (&manager->skeleton);

  G_OBJECT_CLASS (meta_monitor_manager_parent_class)->dispose (object);
}

static void
meta_monitor_manager_class_init (MetaMonitorManagerClass *klass)
{
  GObjectClass *object_class = G_OBJECT_CLASS (klass);

  object_class->dispose = meta_monitor_manager_dispose;
  object_class->finalize = meta_monitor_manager_finalize;

  signals[MONITORS_CHANGED] =
    g_signal_new ("monitors-changed",
		  G_TYPE_FROM_CLASS (object_class),
		  G_SIGNAL_RUN_LAST,
		  0,
                  NULL, NULL, NULL,
		  G_TYPE_NONE, 0);
}

static const double known_diagonals[] = {
    12.1,
    13.3,
    15.6
};

static char *
diagonal_to_str (double d)
{
  unsigned int i;

  for (i = 0; i < G_N_ELEMENTS (known_diagonals); i++)
    {
      double delta;

      delta = fabs(known_diagonals[i] - d);
      if (delta < 0.1)
        return g_strdup_printf ("%0.1lf\"", known_diagonals[i]);
    }

  return g_strdup_printf ("%d\"", (int) (d + 0.5));
}

static char *
make_display_name (MetaOutput *output)
{
  if (output->width_mm != -1 && output->height_mm != -1)
    {
      double d = sqrt (output->width_mm * output->width_mm +
                       output->height_mm * output->height_mm);
      char *inches = diagonal_to_str (d / 25.4);
      char *ret;

      ret = g_strdup_printf ("%s %s", output->vendor, inches);

      g_free (inches);
      return ret;
    }
  else
    {
      return g_strdup (output->vendor);
    }
}

static gboolean
handle_get_resources (MetaDBusDisplayConfig *skeleton,
                      GDBusMethodInvocation *invocation,
                      MetaMonitorManager    *manager)
{
  GVariantBuilder crtc_builder, output_builder, mode_builder;
  unsigned int i, j;

  g_variant_builder_init (&crtc_builder, G_VARIANT_TYPE ("a(uxiiiiiuaua{sv})"));
  g_variant_builder_init (&output_builder, G_VARIANT_TYPE ("a(uxiausaua{sv})"));
  g_variant_builder_init (&mode_builder, G_VARIANT_TYPE ("a(uxuud)"));

  for (i = 0; i < manager->n_crtcs; i++)
    {
      MetaCRTC *crtc = &manager->crtcs[i];
      GVariantBuilder transforms;

      g_variant_builder_init (&transforms, G_VARIANT_TYPE ("au"));
      g_variant_builder_add (&transforms, "u", 0); /* 0 = WL_OUTPUT_TRANSFORM_NORMAL */

      g_variant_builder_add (&crtc_builder, "(uxiiiiiuaua{sv})",
                             i, /* ID */
                             crtc->crtc_id,
                             (int)crtc->rect.x,
                             (int)crtc->rect.y,
                             (int)crtc->rect.width,
                             (int)crtc->rect.height,
                             (int)(crtc->current_mode ? crtc->current_mode - manager->modes : -1),
                             0, /* 0 = WL_OUTPUT_TRANSFORM_NORMAL */
                             &transforms,
                             NULL /* properties */);
    }

  for (i = 0; i < manager->n_outputs; i++)
    {
      MetaOutput *output = &manager->outputs[i];
      GVariantBuilder crtcs, modes, properties;

      g_variant_builder_init (&crtcs, G_VARIANT_TYPE ("au"));
      for (j = 0; j < output->n_possible_crtcs; j++)
        g_variant_builder_add (&crtcs, "u",
                               (unsigned)(output->possible_crtcs[j] - manager->crtcs));

      g_variant_builder_init (&modes, G_VARIANT_TYPE ("au"));
      for (j = 0; j < output->n_modes; j++)
        g_variant_builder_add (&modes, "u",
                               (unsigned)(output->modes[j] - manager->modes));

      g_variant_builder_init (&properties, G_VARIANT_TYPE ("a{sv}"));
      g_variant_builder_add (&properties, "{sv}", "vendor",
                             g_variant_new_string (output->vendor));
      g_variant_builder_add (&properties, "{sv}", "product",
                             g_variant_new_string (output->product));
      g_variant_builder_add (&properties, "{sv}", "serial",
                             g_variant_new_string (output->serial));
      g_variant_builder_add (&properties, "{sv}", "display-name",
                             g_variant_new_take_string (make_display_name (output)));
      g_variant_builder_add (&properties, "{sv}", "primary",
                             g_variant_new_boolean (output->is_primary));
      g_variant_builder_add (&properties, "{sv}", "presentation",
                             g_variant_new_boolean (output->is_presentation));

      g_variant_builder_add (&output_builder, "(uxiausaua{sv})",
                             i, /* ID */
                             output->output_id,
                             (int)(output->crtc ? output->crtc - manager->crtcs : -1),
                             &crtcs,
                             output->name,
                             &modes,
                             &properties);
    }

  for (i = 0; i < manager->n_modes; i++)
    {
      MetaMonitorMode *mode = &manager->modes[i];

      g_variant_builder_add (&mode_builder, "(uxuud)",
                             i, /* ID */
                             mode->mode_id,
                             mode->width,
                             mode->height,
                             (double)mode->refresh_rate);
    }

  meta_dbus_display_config_complete_get_resources (skeleton,
                                                   invocation,
                                                   manager->serial,
                                                   g_variant_builder_end (&crtc_builder),
                                                   g_variant_builder_end (&output_builder),
                                                   g_variant_builder_end (&mode_builder));
  return FALSE;
}                     

static void
on_bus_acquired (GDBusConnection *connection,
                 const char      *name,
                 gpointer         user_data)
{
  MetaMonitorManager *manager = user_data;

  manager->skeleton = META_DBUS_DISPLAY_CONFIG (meta_dbus_display_config_skeleton_new ());

  g_signal_connect_object (manager->skeleton, "handle-get-resources",
                           G_CALLBACK (handle_get_resources), manager, 0);

  g_dbus_interface_skeleton_export (G_DBUS_INTERFACE_SKELETON (manager->skeleton),
                                    connection,
                                    "/org/gnome/Mutter/DisplayConfig",
                                    NULL);
}

static void
on_name_acquired (GDBusConnection *connection,
                  const char      *name,
                  gpointer         user_data)
{
  meta_topic (META_DEBUG_DBUS, "Acquired name %s\n", name);
}

static void
on_name_lost (GDBusConnection *connection,
              const char      *name,
              gpointer         user_data)
{
  meta_topic (META_DEBUG_DBUS, "Lost or failed to acquire name %s\n", name);
}

static void
initialize_dbus_interface (MetaMonitorManager *manager)
{
  manager->dbus_name_id = g_bus_own_name (G_BUS_TYPE_SESSION,
                                          "org.gnome.Mutter.DisplayConfig",
                                          G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT |
                                          (meta_get_replace_current_wm () ?
                                           G_BUS_NAME_OWNER_FLAGS_REPLACE : 0),
                                          on_bus_acquired,
                                          on_name_acquired,
                                          on_name_lost,
                                          g_object_ref (manager),
                                          g_object_unref);
}

static MetaMonitorManager *global_monitor_manager;

void
meta_monitor_manager_initialize (Display *display)
{
  global_monitor_manager = meta_monitor_manager_new (display);

  initialize_dbus_interface (global_monitor_manager);
}

MetaMonitorManager *
meta_monitor_manager_get (void)
{
  g_assert (global_monitor_manager != NULL);

  return global_monitor_manager;
}

MetaMonitorInfo *
meta_monitor_manager_get_monitor_infos (MetaMonitorManager *manager,
                                        int                *n_infos)
{
  *n_infos = manager->n_monitor_infos;
  return manager->monitor_infos;
}

MetaOutput *
meta_monitor_manager_get_outputs (MetaMonitorManager *manager,
                                  int                *n_outputs)
{
  *n_outputs = manager->n_outputs;
  return manager->outputs;
}

int
meta_monitor_manager_get_primary_index (MetaMonitorManager *manager)
{
  return manager->primary_monitor_index;
}

void
meta_monitor_manager_invalidate (MetaMonitorManager *manager)
{
  MetaOutput *old_outputs;
  MetaCRTC *old_crtcs;
  MetaMonitorInfo *old_monitor_infos;
  MetaMonitorMode *old_modes;
  int n_old_outputs;

  /* Save the old structures, so they stay valid during the update */
  old_outputs = manager->outputs;
  n_old_outputs = manager->n_outputs;
  old_monitor_infos = manager->monitor_infos;
  old_modes = manager->modes;
  old_crtcs = manager->crtcs;

  manager->serial ++;
  read_current_config (manager);
  make_logical_config (manager);

  g_signal_emit (manager, signals[MONITORS_CHANGED], 0);

  g_free (old_monitor_infos);
  free_output_array (old_outputs, n_old_outputs);
  g_free (old_modes);
  g_free (old_crtcs);
}